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      07-21-2012, 01:05 AM   #1
Vybz
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Post RPI GTC Exhaust Review

So as some of you might have known, I've been in the market for a new exhaust for a while. I ordered the RPI GTC last week and as of about 6pm today I finished installing it. I had been bouncing back and forth in my mind between the GTC and the GTM. I decided against the GTM because of the drone people kept complaining about in the low rpms. The GTC seemed like it would be all the pros with none of the cons.

Initial impression:

I can feel an increase in power, but I wasn't able to TRULY test it out so I'll get back to that topic down the road. The GTC & GTM claim +28 rwhp and +35 ft/lbs tq and if you remember I recently got my car dyno'ed while it was bone stock. It was for this exact reason, so we will see if RPI is true to their claim.

Installation was cake, everything bolted right where OEM was, and fitment was perfect. The only thing that you have to keep in mind is that you do need to utilize the OEM exhaust clamps to connect the x pipe to the connecting pipes.

Now for sound. So I started the car windows up, and I immediately was like ... damn should have gone with the GTM lol. ( I think my opinion though at that time was a little biased though, because for the last week, I've been rolling with only the stock x-pipe on the car and no muffler... needless to say that was very loud ). As soon as I started to pull away though I could immediately hear the change. 3k rpm and below and the exhaust is as docile as can be, head towards WOT and the exhaust screams.
I never really understood the description of "deep french horn overtone" until today. It is definitely loud when you want it to be. Ironically after I installed the exhaust I went out to eat and when I was leaving the restaurant, I set off the alarm of the truck parked next to me upon start up .
On the topic of drone ... there is none. The GTC truly fixes that aspect of the GTM. If I wanted to, I could drive around conservatively and make the car sound stock. There are times I wish it was a tad more aggressive (really only when I'm rev-matching) , but I'm sure the car is MUCH louder from outside then from within the cabin.


I plan on doing a full and proper review, and I know everything above doesn't mean anything without sound clips. I'll get them to the community asap and It'll be in a variety of situations and environments so you can get the best idea of what the exhaust sounds like.

I'll be heading back to the shop to get the car dyno'ed so I'll also post the exhausts TRUE gains when I have the new numbers.

Here's a link to my stock dyno pull if you missed it, the numbers are in the description. The workhorse had some impressive numbers for stock so if the GTC truly adds it's figures on to that, I'll be impressed and I'll be that much closer to my goal of 400+ rwhp while still NA.



I'll continue to update this post as information rolls in.
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      07-21-2012, 10:15 PM   #2
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sounds good.
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      07-22-2012, 12:19 AM   #3
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i've been waiting for a review. Please update when you can.
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      07-22-2012, 01:12 AM   #4
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Congrats! Enjoy
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      07-22-2012, 02:06 AM   #5
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What's the difference between gtc and gtm? Race vs sport?
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      07-22-2012, 09:38 AM   #6
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What's the difference between gtc and gtm? Race vs sport?
The only difference between GTM and GTC is that the GTC has a customized muffler with laser cut end caps. It maintains the same performance specs as GTM, but is 20-30% quieter.

It's essentially just a custom GTM, that's more daily driven friendly.
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      07-22-2012, 09:40 AM   #7
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lol thanks Krozi Your input definitely help guide me in my decision. I feel I made the right choice, but I'm not going to lie, I'm curious as to what a GTM sounds like.
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      07-22-2012, 10:52 AM   #8
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nice...looking forward to your dyno numbers....

if the gtc was around when i was in the market for an exhaust I might have gone that route as well...as it seems like it's a good DD exhaust, especially when compared with the GTM and GT RPI systems....

enjoy..

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      08-15-2012, 03:49 PM   #9
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Do you have the full exhaust or the axle-back? I am thinking of changing out my Dinan muffler with the axle back version of the GTC. I am running a Challenge Street X-Pipe with my Dinan and love the sound, but am looking for something a bit more aggressive looking for aesthetics.

Let me know your thoughts, and thanks in advance.
Chris
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      08-15-2012, 07:18 PM   #10
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Quote:
Originally Posted by iamcpap View Post
Do you have the full exhaust or the axle-back? I am thinking of changing out my Dinan muffler with the axle back version of the GTC. I am running a Challenge Street X-Pipe with my Dinan and love the sound, but am looking for something a bit more aggressive looking for aesthetics.

Let me know your thoughts, and thanks in advance.
Chris
I have the full exhaust. lol I've been so focused on getting sound clips I completely forgot to take pictures of it on the car. It's definitely an aggressive look, in comparison to stock and IMO looks more aggressive from the rear as well (especially with the wider tips, but also because the mufflers stand out significantly more then stock).

I have a vid with highway and tunnel pulls that's almost ready ( need to cut out the filler) . I can throw up pics of the exhaust on the car today and with any luck it should be enough to guide you in your decision.
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      08-15-2012, 08:47 PM   #11
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Please update when you can
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      08-16-2012, 02:06 AM   #12
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Nicely done Vybz! Can't wait to see some pics and vids..
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      08-16-2012, 09:46 PM   #13
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Quote:
Originally Posted by iamcpap View Post
I am running a Challenge Street X-Pipe with my Dinan and love the sound, but am looking for something a bit more aggressive looking for aesthetics.

Let me know your thoughts, and thanks in advance.
Chris









Sorry for the crappy smart phone pics, but I wanted to get you an idea asap, and my mind was encouraging me to wait till I detailed the car this Saturday before I posted pics. lol... so as you can see the car is crazy dirty in the pics, but I'm heading to a Griots Garage car meet on Sunday, and I'll be able to get better pics, plus most likely get some vids to you then.
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      08-18-2012, 01:32 PM   #14
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Quote:
Originally Posted by Vybz View Post









Sorry for the crappy smart phone pics, but I wanted to get you an idea asap, and my mind was encouraging me to wait till I detailed the car this Saturday before I posted pics. lol... so as you can see the car is crazy dirty in the pics, but I'm heading to a Griots Garage car meet on Sunday, and I'll be able to get better pics, plus most likely get some vids to you then.
I thought I was already over changing the Dinan, but these pics just made mt start thinking again. Definitely more aggressive looking... HMMMMM...
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      08-18-2012, 06:13 PM   #15
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Any dyno updates?
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      08-19-2012, 03:38 PM   #16
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In for vids
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      08-19-2012, 08:54 PM   #17
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Your input definitely help guide me in my decision
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      08-26-2012, 01:53 PM   #18
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Any dyno updates?
Went back to Intec Racing yesterday to dyno the car again.





Unfortunately the gains were ... how can I put this... non existent? It was a hot day, I really wish I had recorded the temperature from my previous pull, and they did replace the fan that they usually have with that small one you can see in front of my car in the video, so I'm not going to consider this to be a truly valid dyno pull due to heat soak and inadequate air flow. We all know removing your cats is the easiest way to see instant numbers, so I find it very hard to believe that without primaries, secondaries, or resonators I'm making the exact same hp as I was stock.

I'll be taking the car to Carb Conn, they have a dynojet 248c just like Intec Racing, and I should be able to get some cross data, because needless to say it was a very disappointing dyno session.

There is a plus though! You can compare my 1st dyno video and 2nd dyno video for exhaust sound, it's like night and day
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      08-26-2012, 09:58 PM   #19
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Your input definitely help guide me in my decision
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      08-28-2012, 11:03 AM   #20
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      08-28-2012, 10:13 PM   #21
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i've been waiting for a review
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      10-03-2012, 10:58 PM   #22
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have to bump this. any more thoughts on this setup? better dyno numbers?
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